I need a scenario for a small dialog-based game / interactive story. The game would be used as an example for a middleware tool we're developing.

I would like to buy an existing story (it should be dynamic of course — with branching dialogs etc.), or hire someone to write a new one.

Please advise, where to go to find such person / service? We're based in Russia, so getting a talented enough native English writer locally is a bit of a problem.

Update: To be extra clear: We must get all necessary rights to reuse the story and make a derived work (i.e. the game we're talking about) from it. This is a commercial product. Borrowing someone else's work at random and using it just not going to work.